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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 109 records · Page 6
All sourcesNASA NTRSDOE OSTI
NASA NTRS1995

Application of NASA's Advanced Life Support Technologies for Waste Treatment, Water Purification and Recycle, and Food Production in Polar Regions

NASA's advanced life support technologies are being combined with Arctic science and engineering knowledge to address the unique needs of the remote communities of Alaska through the Advanced Life Systems for Extreme Environments (ALSEE) project. ALSEE is a collaborative effort involving NASA, the State of Alaska, the University of Alaska, the North Slope Borough of Alaska, and the National Science Foundation (NSF). The focus is a major issue in the state of Alaska and other areas of the Circumpolar North, the health and welfare of its people, their lives and the subsistence lifestyle in remote communities, economic opportunity, and care for the environment. The project primarily provides treatment and reduction of waste, purification and recycling of water. and production of food. A testbed is being established to demonstrate the technologies which will enable safe, healthy, and autonomous function of remote communities and to establish the base for commercial development of the resulting technology into new industries. The challenge is to implement the technological capabilities in a manner compatible with the social and economic structures of the native communities, the state, and the commercial sector. Additional information is contained in the original extended abstract.

Bubenheim, David L.↗
NASA NTRS1988

Search for Martian fossil communities: Science strategies, sediment sites, and sample handling

The strategy for locating and sampling possible fossilized Martian organisms benefits from our experience with fossil microbial ecosystems on Earth. Evidence of early life is typically preserved as stromatolites in carbonates and cherts, and as microfossils in cherts, carbonates and shales. Stromatolites, which are laminated flat or domal structures built by microbial communities, are very likely the oldest and most widespread relics of early life. These communities flourished in supratidal to subtidal coastal benthic environments, wherever sunlight was available and where incoming sediments were insufficient to bury the communities before they became established. A logical site for such communities on Mars might be those areas in an ancient lake bed which were furthest from sediment input, but were still sufficiently shallow to have received sunlight. Therefore, although some sites within Valles Marineris might have contained ponded water, the possibly abundant sediment inputs might have overwhelmed stromatolite-like communities. Localized depressions which acted as catchment basins for ancient branched valley systems might be superior sites. Perhaps such depressions received drainage which, because of the relatively modest water discharges implied for these streams, was relatively low in transported sediment. Multiple streams converging on a single basin might have been able to maintain a shallow water environment for extended periods of time.

Desmarais, David J.↗
NASA NTRSDate not supplied

The Effect of Fiber-Angle Fidelity on the Linear Response of Tow-steered Composite Plates

Composite laminate tailoring is traditionally performed by uniformly changing the in-plane ply orientation to obtain the desired mechanical performance. The emergence of tow-steered plies, where the fibers follow a prescribed curvilinear path, have increased the tailorability of composite laminates. However, characterizing the behavior of tow-steered laminates using finite element analysis is challenging because additional, and often numerous, orientation definitions may be required. The additional orientation definitions detrimentally increase the computational cost and hinder the use of advanced analysis techniques, such as Monte Carlo or uncertainty quantification, in the design process. To reduce computational cost without adversely affecting mechanics-based performance, the results of a parametric study that was used to investigate the effects of fiber-angle fidelity, element size, and tow-steered radius-of-curvature on various loading scenarios for tow-steered composite plates are presented. The three loading scenarios that were analyzed using finite element analysis included an axial tension load, an applied constant through-thickness-direction pressure load, and an axial compression load. Results for mechanics-based metrics of interest are presented and discussed for each loading scenario. Little sensitivity (less than one percent difference) to the effect of fiber-angle fidelity is observed in the mechanics-based metrics until the coarse-end of the considered range. Sensitivity to element size generally dominates the observed results for the mechanics-based metrics. Notable reductions in the preprocessing time are observed for increasingly coarse element size and fiber-rounding parameters. The preprocessing times decreased up to three orders of magnitude from a few thousand seconds to a few seconds without loss of accuracy in the mechanics-based metrics. Such increased computational performance is of particular interest to the structural design and analysis communities that may be conducting large counts of finite-element analyses, such as in other parametric studies, Monte-Carlo analyses, uncertainty quantification, or tow-steered optimization.

tow-steered composites↗
NASA NTRS1981

Technology development status at McDonnell Douglas

The significant technology items of the Concorde and the conceptual MCD baseline advanced supersonic transport are compared. The four major improvements are in the areas of range performance, structures (materials), aerodynamics, and in community noise. Presentation charts show aerodynamic efficiency; the reoptimized wing; low scale lift/drag ratio; control systems; structural modeling and analysis; weight and cost comparisons for superplasticity diffusion bonded titanium sandwich structures and for aluminum brazed titanium honeycomb structures; operating cost reduction; suppressor nozzles; noise reduction and range; the bicone inlet; a market summary; environmental issues; high priority items; the titanium wing and fuselage test components; and technology validation.

Rowe, W. T.↗
NASA NTRS1992

Space Transportation Materials and Structures Technology Workshop. Volume 1: Executive summary

The workshop was held to provide a forum for communication within the space materials and structures technology developer and user communities. Workshop participants were organized into a Vehicle Technology Requirements session and three working panels: Materials and Structures Technologies for Vehicle Systems; Propulsion Systems; and Entry Systems. The goals accomplished were (1) to develop important strategic planning information necessary to transition materials and structures technologies from lab research programs into robust and affordable operational systems; (2) to provide a forum for the exchange of information and ideas between technology developers and users; and (3) to provide senior NASA management with a review of current space transportation programs, related subjects, and specific technology needs. The workshop thus provided a foundation on which a NASA and industry effort to address space transportation materials and structures technologies can grow.

Cazier, F. W., Jr.↗
NASA NTRS1993

Space Transportation Materials and Structures Technology Workshop: Proceedings - Volume 2

The Space Transportation Materials and Structures Technology Workshop was held on September 23-26, 1991, in Newport News, Virginia. The workshop, sponsored by the NASA Office of Space Flight and the NASA Office of Aeronautics and Space Technology, was held to provide a forum for communication within the space materials and structures technology developer and user communities. Workshop participants were organized into a Vehicle Technology Requirements session and three working panels: Materials and Structures Technologies for Vehicle Systems, Propulsion Systems, and Entry Systems.

Cazier, Frank W., Jr.↗
NASA NTRS1985

Microgravity Science and Applications Program Tasks, 1984 Revision

This report is a compilation of the active research tasks as of the end of the fiscal year 1984 of the Microgravity Science and Applications Program, NASA-Office of Space Science and Applications, involving several NASA centers and other organizations. The purpose of the document is to provide an overview of the program scope for managers and scientists in industry, university, and government communities. The report is structured to include an introductory description of the program, strategy and overall goal; identification of the organizational structures and people involved; and a description of each research task, together with a list of recent publications. The tasks are grouped into six categories: (1) electronic materials; (2) solidification of metals, alloys, and composites; (3) fluid dynamics and transports; (4) biotechnology; (5) glasses and ceramics; and (6) combustion.

Elizabeth Pentecost↗
NASA NTRS1989

Microbial trace fossils in Antarctica and the search for evidence of early life on Mars

It is possible to hypothesize that, if microbial life evolved on early Mars, fossil remnants of these organisms may be preserved on the surface. However, the cooling and drying of Mars probably resembled a cold desert and such an environment is not suitable for the process of fossilization. The frigid Ross Desert of Antarctica is probably the closest terrestrial analog to conditions that may have prevailed on the surface of the cooling and drying Mars. In this desert, cryptoendolithic microbial communities live in the airspaces of porous rocks, the last habitable niche in a hostile outside environment. The organisms produce characteristic chemical and physical changes in the rock substrate. Environmental changes (deterioration of conditions) may result in the death of the community. Although no cellular structures are fossilized, the conspicuous changes in the rock substrate are preserved as trace fossils. Likewise, microbial trace fossils (without cellular structures) may also be preserved on Mars: Discontinuities in structure or chemistry of the rock that are independent of physical or chemical gradients may be of biological origin. Ross Desert trace fossils can be used as a model for planning search strategies and for instrument design to find evidence of past Martian life.

Friedmann, E. Imre↗
NASA NTRS1991

Dynamic Analyses Including Joints Of Truss Structures

Method for mathematically modeling joints to assess influences of joints on dynamic response of truss structures developed in study. Only structures with low-frequency oscillations considered; only Coulomb friction and viscous damping included in analysis. Focus of effort to obtain finite-element mathematical models of joints exhibiting load-vs.-deflection behavior similar to measured load-vs.-deflection behavior of real joints. Experiments performed to determine stiffness and damping nonlinearities typical of joint hardware. Algorithm for computing coefficients of analytical joint models based on test data developed to enable study of linear and nonlinear effects of joints on global structural response. Besides intended application to large space structures, applications in nonaerospace community include ground-based antennas and earthquake-resistant steel-framed buildings.

Belvin, W. Keith↗
NASA NTRS2004

Microbial structural diversity estimated by dilution-extinction of phenotypic traits and T-RFLP analysis along a land-use intensification gradient

The present work tested whether the relationship between functional traits and inoculum density reflected structural diversity in bacterial communities from a land-use intensification gradient applying a mathematical model. Terminal restriction fragment length polymorphism (T-RFLP) analysis was also performed to provide an independent assessment of species richness. Successive 10-fold dilutions of a soil suspension were inoculated onto Biolog GN(R) microplates. Soil bacterial density was determined by total cell and plate counts. The relationship between phenotypic traits and inoculum density fit the model, allowing the estimation of maximal phenotypic potential (Rmax) and inoculum density (KI) at which Rmax will be half-reduced. Though Rmax decreased with time elapsed since clearing of native vegetation, KI remained high in two of the disturbed sites. The genetic pool of bacterial community did not experience a significant reduction, but the active fraction responding in the Biolog assay was adversely affected, suggesting a reduction in the functional potential. c2004 Federation of European Microbiological Societies. Published by Elsevier B.V. All rights reserved.

NASA Center KSC↗
NASA NTRS2011

PRSEUS Development for the Hybrid Wing Body Aircraft

NASA has created the Environmentally Responsible Aviation (ERA) Project to explore and document the feasibility, benefits and technical risk of advanced vehicle configurations and enabling technologies that will reduce the impact of aviation on the environment. A critical aspect of this pursuit is the development of a lighter, more robust airframe that will enable the introduction of unconventional aircraft configurations that have higher lift to drag ratios, reduced drag, and lower community noise. The primary structural concept being developed for the Hybrid Wing Body aircraft design under the ERA project in the Airframe Technology element is the PRSEUS concept. This paper describes how researchers at NASA and Boeing are working together to develop fundamental PRSEUS technologies that could someday be implemented on a transport size HWB airplane design.

Velicki, Alex↗
NASA NTRS2022

Adaptation to environmental extremes structures functional traits in biological soil crust and hypolithic microbial communities

Biological soil crusts (biocrusts) are widespread in drylands and deserts. At the microhabitat scale, they also host hypolithic communities that live under semi-translucent stones. Both environmental niches experience exposure to extreme conditions such as high UV radiation, desiccation, temperature fluctuations, and resource limitation. However, hypolithic communities are somewhat protected from extremes relative to biocrust communities. Conditions are otherwise similar, so comparing them can answer outstanding questions regarding adaptations to environmental extremes. Using metagenomic sequencing, we assessed the functional potential of dryland soil communities and identified the functional underpinnings of ecological niche differentiation in biocrusts versus hypoliths. We also determined the effect of the anchoring photoautotroph (moss or cyanobacteria). Genes and pathways differing in abundance between biocrusts and hypoliths indicate that biocrust communities adapt to the higher levels of UV radiation, desiccation, and temperature extremes through an increased ability to repair damaged DNA, sense and respond to environmental stimuli, and interact with other community members and the environment. Intracellular competition appears to be crucial to both communities, with biocrust communities waging war using the Type VI Secretion System (T6SS) and hypoliths favoring diversity of antibiotics. The dominant primary producer had a reduced effect on community functional potential compared with niche, but an abundance of genes related to monosaccharide, amino acid, and osmoprotectant uptake in moss-dominated communities indicates reliance on resources provided to heterotrophs by mosses. Our findings indicate that functional traits in dryland communities are driven by adaptations to extremes and we identify strategies that likely enable survival in dryland ecosystems.

Biological soil crusts↗
NASA NTRS2011

Microbial Diversity Analysis of the Bacterial and Archaeal Population in Present Day Stromatolites

Stromatolites are layered sedimentary structures resulting from microbial mat communities that remove carbon dioxide from their environment and biomineralize it as calcium carbonate. Although prevalent in the fossil record, stromatolites are rare in the modem world and are only found in a few locations including Highbome Cay in the Bahamas. The stromatolites found at this shallow marine site are analogs to ancient microbial mat ecosystems abundant in the Precambrian period on ancient Earth. To understand how stromatolites form and develop, it is important to identify what microorganisms are present in these mats, and how these microbes contribute to geological structure. These results will provide insight into the molecular and geochemical processes of microbial communities that prevailed on ancient Earth. Since stromatolites are formed by lithifying microbial mats that are able to mineralize calcium carbonate, understanding the biological mechanisms involved may lead to the development of carbon sequestration technologies that will be applicable in human spaceflight, as well as improve our understanding of global climate and its sustainability. The objective of my project was to analyze the archaeal and bacterial dIversity in stromatolites from Highborn Cay in the Bahamas. The first step in studying the molecular processes that the microorganisms carry out is to ascertain the microbial complexity within the mats, which includes identifying and estimating the numbers of different microbes that comprise these mats.

Ortega, Maya C.↗
NASA NTRS1998

Crystal growth and crystallography

Selected topics that may be of interest for both crystal-structure and crystal-growth communities are overviewed. The growth of protein crystals, along with that of some other compounds, is one of the topics, and recent insights into related phenomena are considered as examples of applications of general principles. The relationship between crystal growth shape and structure is reviewed and an attempt to introduce semiquantitative characterization of binding for proteins is made. The concept of kinks for complex structures is briefly discussed. Even at sufficiently low supersaturations, the fluctuation of steps may not be sufficient to implement the Gibbs-Thomson law if the kink density is low enough. Subsurface ordering of liquids and growth of rough interfaces from melts is discussed. Crystals growing in microgravity from solution should be more perfect if they preferentially trap stress-inducing impurities, thus creating an impurity-depleted zone around themselves. Evidently, such a zone is developed only around the crystals growing in the absence of convection. Under terrestrial conditions, the self-purified depleted zone is destroyed by convection, the crystal traps more impurity and grows stressed. The stress relief causes mosaicity. In systems containing stress-inducing but poorly trapped impurities, the crystals grown in the absence of convection should be worse than those of their terrestrial counterparts.

Review, Tutorial↗
NASA NTRS2013

Status of Advanced Stitched Unitized Composite Aircraft Structures

NASA has created the Environmentally Responsible Aviation (ERA) Project to explore and document the feasibility, benefits and technical risk of advanced vehicle configurations and enabling technologies that will reduce the impact of aviation on the environment. A critical aspect of this pursuit is the development of a lighter, more robust airframe that will enable the introduction of unconventional aircraft configurations that have higher lift-to-drag ratios, reduced drag, and lower community noise levels. The primary structural concept being developed under the ERA project in the Airframe Technology element is the Pultruded Rod Stitched Efficient Unitized Structure (PRSEUS) concept. This paper describes how researchers at NASA and The Boeing Company are working together to develop fundamental PRSEUS technologies that could someday be implemented on a transport size aircraft with high aspect ratio wings or unconventional shapes such as a hybrid wing body airplane design.

Jegley, Dawn C.↗
NASA NTRS2000

Investigations into an unknown organism on the martian meteorite Allan Hills 84001

Examination of fracture surfaces near the fusion crust of the martian meteorite Allan Hills (ALH) 84001 have been conducted using scanning electron microscopy (SEM) and atomic force microscopy (AFM) and has revealed structures strongly resembling mycelium. These structures were compared with similar structures found in Antarctic cryptoendolithic communities. On morphology alone, we conclude that these features are not only terrestrial in origin but probably belong to a member of the Actinomycetales, which we consider was introduced during the Antarctic residency of this meteorite. If true, this is the first documented account of terrestrial microbial activity within a meteorite from the Antarctic blue ice fields. These structures, however, do not bear any resemblance to those postulated to be martian biota, although they are a probable source of the organic contaminants previously reported in this meteorite.

NASA Center JSC↗
NASA NTRS2003

Centennial of Flight Educational Outreach

The Centennial of Flight Education Outreach project worked with community partners to disseminate NASA Education materials and the Centennial of Flight CD-ROM as a vehicle to increase national awareness of NASA's Aerospace Education products, services and programs. The Azimuth Education Foundation and the Ninety Nines, an International Women Pilots Association, Inc. were chartered to conduct education outreach to the formal and informal educational community. The Dryden Education Office supported the development of a training and information distribution program that established a national group of prepared Centennial of Flight Ambassadors, with a mission of community education outreach. These Ambassadors are members of the Ninety Nines and through the Azimuth Foundation, they assisted the AECC on the national level to promote and disseminate Centennial of Flight and other educational products. Our objectives were to explore partnership outreach growth opportunities with consortium efforts between organizations. This project directly responded to the highlights of NASA s Implementation Plan for Education. It was structured to network, involve the community, and provide a solid link to active educators and current students with NASA education information. Licensed female pilots who live and work in local communities across the nation carried the link. This partnership has been extremely gratifying to all of those Ninety-Nines involved, and they eagerly look forward to further work opportunities.

McCarthy, Marianne↗